A printer includes: a printer-side establishment unit; an instruction transmitting unit for transmitting a connection instruction when the printer is to be changed from a first state to a second state; a printer-side notification receiving unit for receiving: a print notification from a notification server when the printer is at the first state; and a changing notification from a proxy server when the printer is at the second state; a change unit for changing the state of the printer as: from the first state to the second state when the connection instruction is transmitted to the proxy server; and from the second state to the first state when the changing notification is received from the proxy server; and a print control unit for controlling a print performing unit to perform printing in accordance with print data when the changing notification is received from the proxy server.